add test and a guard in action translator. minor. Relates to antlr#1143

mmig · Mar 30, 2016 · b78e0e9 · b78e0e9
1 parent cbef19c
commit b78e0e9
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Showing 2 changed files with 12 additions and 2 deletions.
diff --git a/tool-testsuite/test/org/antlr/v4/test/tool/TestActionTranslation.java b/tool-testsuite/test/org/antlr/v4/test/tool/TestActionTranslation.java
@@ -31,6 +31,7 @@
 package org.antlr.v4.test.tool;
 
 import org.antlr.v4.test.runtime.java.BaseTest;
+import org.antlr.v4.tool.Grammar;
 import org.junit.Test;
 
 /** */
@@ -180,6 +181,15 @@ public class TestActionTranslation extends BaseTest {
 		testActions(attributeTemplate, "finally", action, expected);
     }
 
+    @Test public void testEmptyActions() throws Exception {
+	    String gS =
+	   		"grammar A;\n"+
+	   		"a[] : 'a' ;\n" +
+	   		"c : a[] c[] ;\n";
+	    Grammar g = new Grammar(gS);
+    }
+
+
     @Test public void testDynamicRuleScopeRefInSubrule() throws Exception {
         String action = "$a::n;";
     }

diff --git a/tool/src/org/antlr/v4/codegen/ActionTranslator.java b/tool/src/org/antlr/v4/codegen/ActionTranslator.java
@@ -138,7 +138,7 @@ public static List<ActionChunk> translateAction(OutputModelFactory factory,
 													ActionAST node)
 	{
 		String action = tokenWithinAction.getText();
-		if ( action.charAt(0)=='{' ) {
+		if ( action!=null && action.length()>0 && action.charAt(0)=='{' ) {
 			int firstCurly = action.indexOf('{');
 			int lastCurly = action.lastIndexOf('}');
 			if ( firstCurly>=0 && lastCurly>=0 ) {
@@ -158,7 +158,7 @@ public static List<ActionChunk> translateActionChunk(OutputModelFactory factory,
 		translator.rf = rf;
         factory.getGrammar().tool.log("action-translator", "translate " + action);
 		String altLabel = node.getAltLabel();
-		if ( rf!=null ) { 
+		if ( rf!=null ) {
 		    translator.nodeContext = rf.ruleCtx;
 	        if ( altLabel!=null ) translator.nodeContext = rf.altLabelCtxs.get(altLabel);
 		}